The Auburn School Committee is considering a proposal to institute late-start Wednesdays for students in grades 7 through 12.

The proposal, pitched by Superintendent Katy Grondin, means students would come to school at 9:30 a.m. instead of 7:30 a.m. each Wednesday.

Since we’re talking about school, do you feel like doing a word problem?

There are 175 days in the school year, and if students go to school two hours later one day each week, how many hours of school will be subtracted from the total school year?

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The answer is 70 hours.

Or, if you prefer to think of time in days, that’s 10 days.

Maine already has one of the shortest school calendars in the country, and Auburn is discussing shortening it by two weeks for middle and high school students? Why?

This is not, as some districts in the country have done, a move to start late to accomodate teens’ maturing endocrine systems that create a natural late-to-bed, late-to-rise sleep cycle.

This is to give teachers an extra two hours of professional development each week so they can update personal teaching methods.

This time would be in addition to the 3.3 in-school hours high school teachers already have to themselves each week for individual preparation, and 5.6 in-school hours middle school teachers have.

Auburn schools are moving toward a technique called Mass Customized Learning, in which teachers become facilitators for technology-focused, individualized, student-led instruction.

And, Auburn educators say, they must develop new techniques to make this transition.

That’s true.

Professional development is common — and necessary — among licensed professionals, including lawyers, electricians, doctors, dental hygienists, engineers, counselors … the list goes on.

That means extra hours at work, and teachers as an occupational group are reluctant to add hours to the work day without additional pay.

Grondin put it more succinctly for the committee: professional development for teachers means extra cost for time worked.

Why?

Teachers are not hourly workers; they are salaried. And salaried workers, in most other professions, work extra hours to keep up with upgraded technologies, methods and techniques as a personal responsibility to remain job current.

Not only is that contrary to professional development pursuits in many other licensed professions, it’s going to be a real burden for parents.

Grondin says that if families are given enough notice, they can work together to figure out how to get their children to school or figure out who might be available to supervise teens if parents have to get to work.

“If” they have to get to work?

That’s a pretty big assumption that the city’s parents have flexible work schedules. Most do not.

And many of these parents add on personal hours for their own professional development, so it would be galling to think they have to accommodate teachers’ reluctance to do the same.

These teachers are salaried professionals. They can figure out how to pursue job development in their existing schedules.